This invention relates to a device for dispensing a mixture of propellant and product from a pressurised aerosol container. In a preferred application the product is a medicament.
Aerosols containing a mixture of medicament and propellant are commonly used, for example in treating conditions of the upper and lower respiratory tract. For treating such conditions medicaments are dispensed in spray form to a patient by means of an oral or nasal inhalation device comprising a housing or sleeve in which a pressurised aerosol container is located and a mouthpiece or nozzle leads out of the tubular housing. In use, the aerosol container is placed in the housing which is then held by the patient in a more or less upright condition and the mouthpiece or nozzle of the inhalation device is placed in the mouth or nostril of the patient. The patient inhales while operating the aerosol container to open the outlet valve of the container and to dispense medicament from the container through the mouthpiece or nozzle into the mouth or nostril of the patient.
With all such devices, the patient dispenses medicament by pressing on a portion of the aerosol container which protrudes from the housing. When such pressure is exerted, the aerosol container is displaced with respect to the housing thereby to open the outlet valve of the aerosol container. Some patients, for example children, geriatrics, arthritics and the infirm, have difficulty in holding the inhalation device to the mouth or nostril whilst depressing the aerosol container with respect to the housing in order to open the outlet valve. Others have difficulty in coordinating movements of their hands with inhalation and as a result may fail to take the desired dosage of medicament.
It is an object of the present invention to provide a way of making it easier for such patients to dispense medicament from an aerosol container and also to provide a way of substantially enclosing the aerosol container, aerosol housing and mouthpiece or nozzle when the device is not in use.